Folding machines



y 1962 G. I. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6. 1959 5 Sheets-Sheet 1 May 1, 1962 e. 1.FREDHOLM FOLDING MACHINES 5 Sheets-Sheet 2 Filed April 6, 1959 lizz vezzdivr I.F1d)1?/O 6122/ May 1, 1962 G. I. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6, 1959 5 Sheets-Sheet 5 May 1, 1962 G. 1.FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6, 1959 5 Sheets-Sheet 4 7 Fig.10

May 1, 1962 G. 1. FREDHOLM 3,031,780

FOLDING MACHINES Filed April 6. 1959 5 Sheets-Sheet 5 Fig. 11

United rates if r 3,931,?39 Fatented May 1, 1962 3,931,78tl FQLDINGMACHDIES Gunnar Ivar Fredholm, Forfattarvagen 44, Bromma, Sweden FiledApr. 6, 1959, Ser. No. 804,422 Claims priority, application Sweden July19, 1958 1 Claim. (Cl. 38-2) This invention relates to folding machinessuch as are used for folding flatwork in laundries, particularly sheets,table cloths and the like preferably after the ironing of such articlesof fiatwork.

The object of the present invention is to provide an improved machineutilizing a single reciprocating folding blade, which machine requires aminimum of space and is arranged as a unit built into an ironingmachine.

A further object is to provide a device for measuring the length of thefiatwork during that period said work being passed through the ironingmachine, so that no additional space is required for the measuringtrack.

A further object is to provide an improved timing device for the foldingmechanism comprising individually working units which may be started bymeans of impulses delivered by the measuring device, so that one articlecan be measured during the period in which another article has arrivedto the folding device or is being folded.

Further objects of the invention in part are obvious and in part willappear more in detail hereinafter.

in the drawings,

FIGS. 1 to 5 are diagrammatic views showing the several steps in thefolding operation;

FIG. 6 is a perspective view of two timing members for delivering ofimpulses to the folding blade mechanisrn;

FIG. 7 is a diagrammatic side elevation illustrating a part of anironing machine provided with the folding device according to theinvention;

FIG. 8 is a plan view on an enlarged scale of the folding blade and ofone of the two appertaining folding rollers;

FIG. 9 is a side view, partly in section, of the timing device whichcontains three speed controlling units;

FIG. 10 is a sectional elevation of the timing device, the section beingtaken on line 101(l, FIG. 9;

FIG. 11 is a diagrammatic view showing the driving members of thefolding blade and the electric wire diagram connected thereto.

The folding operation will be principally explained, reference beingmade to FIGS. 1 to 6.

In FIG. 1 a conventional fiatwork ironer is shown, including the usualheated platen or chest 1 with which co-operate padded rollers. The lastroller of the ironer is shown in dot-dash lines and designated by 2. Theroller co-operates with the part 3 of the chest arranged at the deliveryend of the ironing machine. From this end the calendered articles aredirectly fed into the folding device. in the FIGURE 1 the letter Arepresents the path which one edge of e.g. a bed sheet performs in theironing machine. B represents the path which the fore edge of the bedsheet performs until the rear edge of the sheet arrives at the input endof the machine. Said distances may of course be measured from a chosenpoint of the track. At the point where the measuring operation iscommenced feeling members are arranged. According to the example shown arow of contacts are used which are caused to break their circuit whenthe sheet passes. The circuit is then closed when the rear edge of thesheet has passed the contacts. The heated platen 1 is aranged as a fixedcontact, the movable contact being formed as a spring normally engagingthe platen and so arranged that the sheet may pass the row of contacts.without resistance.

In FIG. 2 is shown an arm 4 pivoted at 5 upon a fixed axis and at itsend provided with a folding blade 6 which in known manner co-operateswith folding rollers 8 and 9 as shown in FIG. 5. In FIG. 2 the foldingarm 4 is shown in a middle position and the advancing edge of the sheetis hanging freely downward from the rear edge 7 of the chest 3. Afterone-fourth of the length of the sheet has passed over the edge 7 thefolding arm takes the position .shown in FIG. 3 in which the blade 6 ispressed against the sheet at the edge 7 and causes the sheet to bedraped over the folding blade as illustrated in FIG. 4. At the time whenonly one-fourth of the sheet remains in the chest the folding arm takesthe position shown in FIG. 5 in which the folded sheet is fed into thebite of the two folding rollers 8 and 9. The sheet is thereafter inknown manner engaged by the rollers and pulled free from the blade andis delivered on the far side of the rollers in a double fold condition.

The length of the sheet has according to the invention been measuredduring the ironing operation and electric impulses has been deliveredwhen the advancing and the rear edges of the sheet have passed the:feeling contacts. The appertaining circuit is connected to low tension,eg 25 volt DC. The impulses from the feeling contacts are delivered overrelay circuits to the timing device for the folding arm mechanism. Saiddevice and mechanism operate synchronously with the driving shaft of theironing machine.

The lengths A and B may be proposed to correspond to A and B revolutionsof the driving-shaft of the ironer. The timing device is so performedthat the folding arm 4 is moved into the first operative position, shownin FIG. 3, when the fore edge of the bed sheet has passed a distancecorresponding to (A-l-B+ AB) revolutions of the driving-shaft of theironer. When the folding arm 4 under the control of the timing device iscaused to take the second operative position, shown in FIG. 5, the bedsheet has advanced a distance corresponding to revolutions of thedriving-shaft. The described cyclical motions of the folding arm isobtained by means of an auxiliary shaft 19, shown in FIG. 6, which isadapted to complete one single revolution while the driving-shaftperforms A revolutions. The shaft 10 is provided with cam members 11 and12, arranged to actuate electric contact members 13 and M respectively,said contact members being thereby caused to close their circuits. Nowsupposing that the shaft 10 rotates clockwise and the cam members 11 and12 can be set in such angular positions that the cam 11 has to perform adistance up to the contact 13 corresponding to (AB+%.B) of onerevolution and the cam 12 has to nun a distance up to the contact 14corresponding to (AB-}-%B). The cam 11 determines the point when thefolding arm 4 is to be set into the first operative position and the cam12 the point for the second operative position. The shaft 10 will bestarted in the moment in which the rear edge of the bed sheet passes therow of feeling contacts.

The measuring of the length of the sheet is obtained through thedisplacement of the cams 11 and 12 from a fixed starting position.Thereafter current impulses, obtained at the contacts 13 and 14, controlthe timing device during the folding operation so that in a first stageone quarter and in a second stage three-quarters of the length of thesheet have passed the delivery edge 7 of the chest.

The timing device will in such a case be occupied during that period thefore edge of the sheet actuates the feeling contacts until the foldingarm has performed its second stroke. In order to avoid waste of time,due to the fact that the sheets are to be fed to the ironer at intervalscorresponding to 2A revolutions of the driving shaft, the timing devicemay be provided with two or more individually working units. Accordingto the example shown, three such units are connected to a selectorarrangement adapted to deliver current impulses to the timing units inturn. The number of the timing units is on the one hand dependent on thelength of the track A and on'the other hand on the length of the sheet.

FIG. 7 illustrates a part of an ironer machine provided with asupporting standard carrying chests 16 and rollers 17. At the inletbetween the first roller 17 and the appertaining chest 16, a cross bar18 carries a set of yielding contact springs or feelers 19 normallyengaging the chest. The contact springs'or feelers are included in acircuit for transmitting impulses to the timing device.

When the sheet passes the feelers the impulse circuit is opened. Saidcircuit contains a steady current controlled relay as will be moreclosely described in connection with a wire diagram. When the sheetleaves the ironer it slides over the rear edge of the last chest 16 andis received by a conveyor band 20 passing over the two rollers 21 and 22which are journaled in the end frame of the machine.

Said conveyor band delivers the sheet to the folding mechanism in whicha folding lever 23, corresponding to the arm 4 as shown in FIGS. 2 to 5,is provided with a knife-shaped folding blade 24. The folding 'blade isso arranged that it can be moved into a position below the roller 22, asshown in FIG. 7, i.e. into a first operative position. In the secondoperative position the folding blade co-operates with a pair of foldingrollers 25 and 26, of which the lower roller 26 is provided with anumber of conveyer bands 27 running over a roller 23. The last namedconveyer bands deliver the mangled and folded sheet.

The conveyor bands 27 are driven by means of a chain- 'wheel 29 mountedon the roller 23, a chain 30 that encircles both chain-wheel 29, and achain-wheel 31. On the shaft of the wheel 31 further four chain-wheelsare mounted viz. two wheels 31 with the same diameter as the first namedand two wheels 32 with a greater diameter. 'One of the'two wheels 32 is,by means of a chain 33, in driving connection with a chain-wheel 34fixedly connected to the conveyer roller 22. The other of the two wheels32 is driven by a chain-wheel 36, by means of a chain 35, thechain-wheel 36 being mounted on the same shaft as a gear-wheel 37 whichengages a gear-wheel 38 mounted on a stub shaft of the last ironingroller 17. The ironing rollers are in known manner driven by means of amotor (not shown).

By means of a chain 39 and a wheel 40 one of the Wheels 31 is arrangedto drive a shaft 41, when an electromagnetic controlled jaw clutch isactuated, as will be described in connection with FIGS. 9 and 11. Theshaft 41 carries a cam 42 which is adapted to move the folding lever 23into its operative positions corresponding to thepositions of the arm 4in FIGS 4 and 5. The lever 23 is pivoted at 43 on the machine frame andits lower portion 44 engages the cam 42 under the action of a spring 45,the fixed end of which is designated by 46. The

remaining chain wheel 31 drives, by the aid of a chain 47, a doublesprocket 48, 49 the smaller sprocket 49 of the double sprocket beingconnected by a chain 50 with a sprocket 51. The shaft of this last namedsprocket carries a gear wheel 52 meshing with three'gear wheels '53 to55 which are arranged as planet wheels. Thus the sleeves 75 and 76 ofwhich the first named is internally provided with a ring 77 formingbearing for a shaft 78 and the second sleeve surrounds a hollow shaft79. In the hollow shaft a solid shaft 80 is journaled. Each of theshafts 79 and 8% is at its outer end provided with a radially directedcam arm 81 and 82 respectively adapted to engage an axially displaceablerid 83 arranged to actuate a microswitch 84. This switch controls ahalf-revolution clutch mechanism driving the cam 42 for the foldinglever 23.

By means of a planetary gear the shaft 78 is in driving connection withthe holiow shaft 79 as well as the solid shaft 80.

A gear wheel 85 of said plmetary gear is mounted on the inner end ofshaft '78 and arranged to mesh with a planet wheel 86. This wheel isconnected with two further planet wheels 87 and 88 and together withthese wheels arranged rotatable on a common axle-journal 89 fastenedinto the one shank of the U-shaped crank 72. The gear wheels 85 and 86have the same diameter so that the gear ratio is 1:1. The wheel 87meshes with a gear wheel 90 fixedly connected with the solid shaft 80.The wheel 88 drives a wheel 91 on the hollow shaft 79, the gear ratiobeing 3:4. The wheel 91 is fixed to the last named shaft so that saidshaft runs with a gear ratio 3:4, the gear ratio between the wheels 87and 90 and thus the shaft 80 being 1:4. Said gear conditions correspondwith the desired periods for setting of the folding blade into theoperative positions, i.e. in a first moment when one-fourth of thelength of the sheet has passed over the folding blade 24 and in a secondmoment when threequarters of the sheet has passed the blade.

The shaft 78 carries a ratchet 92 fixed to the gear wheel 85 and on saidshaft. The ratchet 92 and thus the shaft 78 and the planet wheels canrotate in relation to the U- shaped crank 72, whereby a helical spring93 is set. The inner end of said spring is fixed in a slot of the shaft78 and the outer end 95 of the spring is connected with a pin insertedinto the crank 72. Under the action of the helical spring a joggle 96 onthe ratchet 92 engages a pin 97 inserted into the crank 72. In a planeparallel with the shanks of the U-shaped crank 72 and parallel with theratchet 92 a latch lever 99 is journaled on a'pin 98 inserted in thecrank 72. The one end of the latch lever is formed as a catch 100normally engaging a recess 101 in the cylindrical inner surface 102 ofthe casing 71. The latch lever is actuated by a spring 103 whichmaintains the lever in engagement withsaid recess 101 so that theU-shaped crank is prevented to rotate in relation to the casing. Thelatch lever carries a pawl 104 journaled on a pin 105 fixed on the latchlever and swingable outwardly in relation to the centre of the ratchetagainst the action of a spring 106 which maintains the pawl in aposition fixed by means of a slot and pin arrangement so that the pawl104 only can engage the ratchet when the latch lever 99 disengages therecess 101. The teeth of the ratchet are so directed that the ratchetcan be turned in the direction marked by an arrow 107 and is preventedto turn in the opposite direction. When the catch 10% is in engagementwith the recess 101 the catch actuates, by means ofa rod108, amicro-switch 109 maintaining the same in. open position. The switchwill, however, close its circuit when the latch lever 99 is actuated bya rod 110 in such a manner that the catch 100 disengages the rod 108.The rod 110 is actuated by a movable armature 111 of an electromagnet112. When this electromagnet is alive the latch lever 99 is held in aposition which permits the catch 100 to move on the cylindrical surface102. Thus the U-shaped crank 72 is allowed to rotate in relation to thecasing 71. In this position of the latch lever the pawl 104 engages theratchet. The rod 110 is actuated by a spring which tends to displace therod outwardly out of engagement with the latch lever and tends to bringthe armature 111 into its rest position. As long as the electromagnet isalive the inner end of the rod 110 is maintained inside the cylindricalsurface 162 so that said end is able to engage a notch 114 on the outeredge of the latch lever. In this way the crank 72 is maintained in thestarting position when the electromagnet is energized.

The main shaft 78 of the planet gear is driven by means of anelectromagnet controlled jaw clutch, the one member 115 of which beingfixed on the shaft 78 and the other member 116 being axiallydisplaceable on a shaft 117 and journaled on that shaft by means of aball-bearing 118. The inner end of the shaft 117 is journaled in a borecentrally arranged in the clutch member 115 and the other end of saidshaft is journaled in a ball-bearing 119, the outer race of which isfixedly mounted in the casing 71. The shaft 117 is axially displaceablein the bearing 119 and actuated by a spring 129 which tends to disengagethe clutch. An armature 122 of an electromagnet 121 is, by means of arod 123, arranged to let in the clutch.

The movable clutch member 116 forms part of a hub portion of the gearwheels 53 shown in FIGS. 7 and 9. The two gear wheels 54 and 55 are eacharranged to drive a timing mechanism 71a and 71b respectively (FIG. 10).

The three timing units 71, 71a and 71b are arranged to be started inturn by means of a selector device which will be described below.

Referring particularly to FIG. 11 and electromagnet 125 is arranged tocontrol a switch 126. The electromagnet is connected up in the circuitof the contact springs 19. When said circuit is closed the electromagnetmaintains the switch 126 in open position. In the moment the sheetengages the springs 19 the circuit is broken and the switch 126 isclosed. Thereby one of the three electromagnets 112 is energized. Theseelectromagnets are connected to a selector provided with a contact arm130 fixed on a driven shaft 131 and co-operating with three fixedcontacts 132 to 134 angularly displaced 120 and each connected to one ofthe electromagnets 112. The selector arm 130 is driven by a steppingmechanism comprising a ratchet wheel 135 driven by a pawl 136 on anoperating lever 138 which is arranged to be attracted by anelectromagnet 137 against the action of a spring 139. When theelectromagnet collapses the spring turns the lever 138 and the ratchetwheel 135 an angle of 120, the selector arm 130 being moved from onecontact to the next of the contacts 132 to 134. The selector arm 13!)and the electromagnet 137 are coupled to the switch 126 in parallel.

When one of the electromagnets 112 is energized the armature 111 of saidelectromagnet turns the latch lever 99 such an angle that themicroswitch 109 is permitted to close its circuit (FIGS. 9 to 11). Owingto this the electromagnet 121 is energized and moves the driving clutchmember 116 into engagement with the clutch member 115 which thereby isrotated, one of the two cam arms 81, 82 being brought to actuate themicroswitch 84 which delivers a current impulse to an electromagnet 146.The armature 141 of the electromagnet is connected with a wedge shapedlatch 142 which, under spring action, engages a recess 143 of a turnablecircular disc 144. Said disc has two diametrically opposed recesses 143and serves as a half-revolution clutch for the shaft 41 carrying the cam42 in the folding mechanism. The latch 142 is arranged to actuate aswitch 145. When the electromagnet 140 is energized the latch 142- isdisengaged closing the switch 145 and thereby connecting up an electromagnet 147 into a circuit 146 which is energized with the terminalvoltage. The armature of the electromagnet 147 causes a jaw clutch 148to be engaged so that the shaft 41 and thus the cam 42 are put indriving connection with a shaft 149 which in turn is driven by the chainwheel 40. This driving means may be performed fundamentally in the samemanner as the jaw clutch 115, 116 controlled by electromagnet 121.

Because the current impulses from the microswitch 84 6 are short, due tothe continuous motion of the cam arms 81 and 82, the armature 141, aftera momentary attraction, must be retained in the attracted position byother means. According to the example shown this is obtained by that therecess 143 has such a depth and the wedge shaped latch has such a lengththat the latch after the disengagement slides on the edge of thecircular disc 144 which at this moment has been set in motion by theengaged jaw clutch 148. Thereby the switch 145 is maintained in closedposition until the latch 142 engages the next recess 143. The disc 144in this manner is permitted to run half a revolution in order to set thefolding blade into one of its operative positions.

The timing mechanism herein described operates as follows:

When the contact springs 19, shown in FIG. 7, are caused to break theimpulse circuit, which occurs when the advancing edge of the sheetengages the springs 19, the switch 126 is closed as marked by dottedlines in FIG. 11. The electromagnet 112 will now be energized so thatthe electromagnet 121 is put in circuit by means of the microswitch 109.The jaw clutch 115, 116, shown in FIG. 9, is engaged and the shaft 78 iscaused to rotate at a speed of one revolution for each A revolution ofthe driving shaft 124. The rod 110 is by means of the electromagnet 112maintained in locking engagement with the notch 114 of the latchinglever 99 as shown in FIG. 10. Hereby the crank 72 is prevented fromrotating in relation to the casing 71. By means of the gear wheels 85,86, 87 and 90 the shaft 78 drives the cam arm 82 at a speed of of thatof the shaft 7 8. By means of the gear wheels 85, 86, 88 and 91 the camarm 81 is rotated in the same direction as the first named cam arm andat a speed of A of that of the shaft 78. The helical spring 93,connecting the ratchet wheel 92 and the crank 72, is stretched.

In the moment the sheet has passed the contact springs 19 the switch 126is caused to break the circuit. The electromagnet 112 now is currentlessand the rod is, by means of its spring 113, brought out of engagementwith the notch 114. The pawl 1114 engages the ratchet wheel 92 so thatthe helical spring 93 is prevented to turn the crank 72 in the directionmarked by the arrow 107 in FIG. 10. Therefore the crank 72, with. itsgear wheels mutually blocked, rotates at the speed of the shaft 78, thelatch 100 sliding along the cylindrical surface 102.

In the moment in which the cam arm. 82 actuates the microswitch 84 theremaining part of the track for said cam arm corresponds to (AB+%B)=(A-%B) of one complete revolution. The microswitch 34 delivers atthis time a current impulse to the electromagnet (FIG. 11) which bringsthe switch into closed position. The half-revolution disc 144 is startedso that the folding blade is brought into its first operative position,shown in FIG. 7. This position corresponds to the blade position shownin FIGS. 3 and 4.

In the moment the latch lever 99 and thus the crank 72 are released bythe rod 110 the remaining part of the track for the cam arm 81corresponds to The cam arm 81 engages momentarily the microswitch 84 andthe disc 144 (FIG. 11) is released and rotates the next half-turnscausing the folding blade to take its second operative position in whichthe blade will force the sheet into the bite of the two folding rollers25 and 26. Said second position of the folding blade is marked in FIG. 7by dash-dotted lines and corresponds to the position shown in FIG. 5.

When the crank 72 has been turned one complete revolution the latch 100of the latch lever engages, under the action of the spring 103 (FIG.10), the rod 108 and the microswitch 109 breaks the circuit. The systemis now currentless and the jaw clutch 115, 116 is under the action ofthe spring 129 disengaged. When the latch lever 7 returns into itsstarting position the pawl 164 is brought out of engagement with theratchet Wheel 92. Thus the helical spring 93 is free to return the gearwheels of the crank 71.. into the starting position, i.e. the positiondeter mined by the joggle 96 of the ratchet Wheel and the pin 97 ofcrank 72.

The timingunit 71 is now ready to receive impulses from the contactsprings 19. Meanwhile the two other timing units 71a and 7L; have beenworking in turn under control of. the selector device including elementsnumbered 31? to 134, inclusive. It will be noted that the switch 126 ismaintained in closed position during that time the sheet is passing thecontact springs 19. When these springs again contact the chest theelectrical system is currentless. As soon as the next sheet engages saidsprings the selector arm 13% is advanced one step coupling up the nexttiming unit into the circuit shown in FIG. 11, so that one sheet can bemeasured during the period in which another sheet is passing the foldingdevice.

It is obvious that many modifications may be made in the arrangement ofthe various parts of the machine and that in particular it is notlimited to the production of a double fold sheet. In addition it alsoshould be mentioned that the cam 42 of the folding mechanism may berotated intermittently by any suitable half revolution mechanismcontrolled by the electromagnet 140.

What I claim is:

A combination ironing and folding machine comprising means to ironflatwork including at least one ironing roller and at least one chestcooperating with said roller, a horizontal discharge roller adjacent thedischarge side of said chest, a pair of folding rollers parallel to andslightly below said discharge roller, said folding rollers being spacedhorizontally from said discharge roller .a distance to permit flatworkdischarged from said discharge rollcr to hangdown between said dischargeroller and said pair of folding rollers, a horizontally movable foldingblade movable back and forth across the horizontal space between thedischarge roller and the folding rollers from a position immediatelybelow said discharge roller toa position to insert flatwork between saidfolding rollers, means to move said blade, a timing mechanism includingfeelers in the path of fiatwork above said chest at the end of saidchest remote from said discharge roller so as to engage said chest orengage said flatwork as it passes through the ironer, said timingmechanism being arranged to activate said means to move said blade fromthe position to insert fiatwork between the folding rollers to itsposition under the discharge roller when substantially a quarter of thelength of a piece of flatwork has passed the level of said foldingblade, and to move said blade from its position under said dischargeroller to its position to insert flatwork in said folding rollers whenan additional half of the length of said fiatwork has passed the levelof said folding blade.

References Cited in the file of this patent UNITED STATES PATENTS1,766,789 Mayer -h June 24, 1930 2,318,252 Myers May 4, 1943 2,330,977Johnson Oct. 5, 1943 2,374,779 Preston May I, 1945 2,464,823 Malott Mar.20, 1949 2,643,879 Spreckelmeier June 30, 1953 2,759,726 SommerhalterAug. 21, 1956

